Survival of the Nicest: Friendly Baboons Live Longest

Survival of the Nicest: Friendly Baboons Live Longest

Baboons, like people, really do get by with a little help from their friends. Humans with strong social ties live longer, healthier lives, whereas hostility and “loner” tendencies can set the stage for disease and early death. In animals, too, strong social networks contribute to longer lives and healthier offspring—and now it seems that personality may be just as big a factor in other primates’ longevity status. A new study found that female baboons that had the most stable relationships with other females weren’t always the highest up in the dominance hierarchy or the ones with close kin around—but they were the nicest.

Scientists are increasingly seeing personality as a key factor in an animal’s ability to survive, adapt, and thrive in its environment. But this topic isn’t an easy one to study scientifically, says primatologist Dorothy Cheney of the University of Pennsylvania. “Research in mammals, birds, fish, and insects shows individual patterns of behavior that can’t be easily explained. But the many studies of personality are based on human traits like conscientiousness, agreeableness, or neuroticism. It isn’t clear how to apply those traits to animals,” Cheney says.

Along with a group of scientists—including co-authors Robert Seyfarth, also at the University of Pennsylvania, and primatologist Joan Silk of Arizona State University, Tempe—Cheney has studied wild baboons at the Moremi Game Reserve in Botswana for almost 20 years. Besides providing detailed, long-term observations of behavior in several generations of baboons, the research has yielded a wealth of biological and genetic information.

In previously published research, Cheney and co-workers showed that females lived longer, had lower stress hormone levels, and had more surviving offspring when they had close, long-lasting relationships with other females (characterized chiefly by spending time together and grooming). Although dominance rank was significant for male baboons—alpha male baboons may live longer than lower-ranking males—this wasn’t true for the females. Nor was an abundance of kin the key to longevity. Not all of the longer-lived, less-stressed females had large families.

Gynne Dyer mentions a group of baboons becoming more peaceful after the dominant males die due to food poisoning brought on to them by their own greed. I can’t find the source of this information other than Dyer’s book. Is this a true story or one drummed up because it sounds plausible and interesting?

I read something similar in Frans de Waal’s Our Inner Ape. I think the story goes that a group of fiercely competetive baboons fought their way through another group of baboons to gain access to a garbage dump that had discarded meat. One day, they ate meat infected with bovine tuberculosis, which killed off the baboons that ate it (i.e., the most aggressive ones that could fight their way to it). Afterward, the troop became harmonious and peaceful for a number of years. This was attributed to a new culture that grew up in the wake of the incident, a culture which was maintained by the females, since none of the males of the original “peaceful” colony were there after 10 years (the males migrated and so were not there to reinforce the new culture). The females, on the other hand,stay in their troops for their entire lives and could therefore have maintained the “peaceful” culture. The fact that females choose which males to allow into the colony may also come into play, as these females may have been more selective toward “peaceable” males. Sorry I don’t have the original citation, but this link might set you on the right track: http://www.nytimes.com/2004/04…